Vieux Farka Toure @ Festival au Desert 2007 (Essekane, Mali) Photo: Damian Rafferty 2008 Central Park Summerstage Shows 06/28/08 View Farka Toure (Tickets TBA) 07/23/08 Mark Knopfler (Presale: 03/14/08 @ 10 AM, Onsale: 03/15/08 @ noon, $70) 07/29/08 Crosby, Stills and Nash (Onsale: 03/29/08 10:00 AM, $66) Check out the rest of the 2008 Central…